English
Related papers

Related papers: How to Morph Graphs on the Torus

200 papers

We develop a theory of confluence of graphs. We describe an algorithm for proving that a given system of reduction rules for abstract graphs and graphs in surfaces is locally confluent. We apply this algorithm to show that each simple Lie…

Quantum Algebra · Mathematics 2014-10-01 Adam S. Sikora , Bruce W. Westbury

By a map we mean a $2$-cell decomposition of a closed compact surface, i.e., an embedding of a graph such that every face is homeomorphic to an open disc. Automorphism of a map can be thought of as a permutation of the vertices which…

Combinatorics · Mathematics 2021-01-08 Ken-ichi Kawarabayashi , Bojan Mohar , Roman Nedela , Peter Zeman

It has been recently shown that any graph of genus g>0 can be stochastically embedded into a distribution over planar graphs, with distortion Olog (g+1)) [Sidiropoulos, FOCS 2010]. This embedding can be computed in polynomial time, provided…

Data Structures and Algorithms · Computer Science 2012-06-22 Yury Makarychev , Anastasios Sidiropoulos

In this paper, we present a constructive and proof-relevant development of graph theory, including the notion of maps, their faces, and maps of graphs embedded in the sphere, in homotopy type theory. This allows us to provide an elementary…

Logic in Computer Science · Computer Science 2024-11-20 Jonathan Prieto-Cubides , Håkon Robbestad Gylterud

Supervised learning on graphs is a challenging task due to the high dimensionality and inherent structural dependencies in the data, where each edge depends on a pair of vertices. Existing conventional methods are designed for standard…

Methodology · Statistics 2024-06-27 Cencheng Shen , Shangsi Wang , Alexandra Badea , Carey E. Priebe , Joshua T. Vogelstein

Trotter and Erd\"os found conditions for when a directed $m \times n$ grid graph on a torus is Hamiltonian. We consider the analogous graphs on a two-holed torus, and study their Hamiltonicity. We find an $\mathcal{O}(n^4)$ algorithm to…

Combinatorics · Mathematics 2016-09-07 Dhruv Rohatgi

Given a set $P$ of $n$ points in the plane, we solve the problems of constructing a geometric planar graph spanning $P$ 1) of minimum degree 2, and 2) which is 2-edge connected, respectively, and has max edge length bounded by a factor of 2…

Discrete Mathematics · Computer Science 2011-12-16 Stefan Dobrev , Evangelos Kranakis , Danny Krizanc , Oscar Morales-Ponce , Ladislav Stacho

We consider the problem of morphing between contact representations of a plane graph. In an $\mathcal F$-contact representation of a plane graph $G$, vertices are realized by internally disjoint elements from a family $\mathcal F$ of…

Computational Geometry · Computer Science 2019-03-19 Patrizio Angelini , Steven Chaplick , Sabine Cornelsen , Giordano Da Lozzo , Vincenzo Roselli

In this paper we study planar morphs between straight-line planar grid drawings of trees. A morph consists of a sequence of morphing steps, where in a morphing step vertices move along straight-line trajectories at constant speed. We show…

Our starting point is the observation that if graphs in a class C have low descriptive complexity in first order logic, then the isomorphism problem for C is solvable by a fast parallel algorithm (essentially, by a simple combinatorial…

Computational Complexity · Computer Science 2007-05-23 Martin Grohe , Oleg Verbitsky

In 2016, Dowden initiated the study of planar Tur\'an-type problems, which has since attracted considerable attention. Recently, Bekos et al. proved that every $K_3$-free $1$-planar graph on $n\ge 4$ vertices has at most $3n-6$ edges. In…

Combinatorics · Mathematics 2026-04-27 Licheng Zhang , Yuanqiu Huang , Fengming Dong

For a drawing of a labeled graph, the rotation of a vertex or crossing is the cyclic order of its incident edges, represented by the labels of their other endpoints. The extended rotation system (ERS) of the drawing is the collection of the…

Given a function $g=g(n)$ we let ${\mathcal E}^g$ be the class of all graphs $G$ such that if $G$ has order $n$ (that is, has $n$ vertices) then it is embeddable in some surface of Euler genus at most $g(n)$, and let ${\widetilde{\mathcal…

Combinatorics · Mathematics 2021-08-11 Colin McDiarmid , Sophia Saller

Graph Isomorphism is one of the classical problems of graph theory for which no deterministic polynomial-time algorithm is currently known, but has been neither proven to be NP-complete. Several heuristic algorithms have been proposed to…

Social and Information Networks · Computer Science 2015-11-23 Natarajan Meghanathan

In this survey, we explore recent literature on finding the cores of higher graphs using geometric and topological means. We study graphs, hypergraphs, and simplicial complexes, all of which are models of higher graphs. We study the notion…

History and Overview · Mathematics 2025-06-30 Inés García-Redondo , Claudia Landi , Sarah Percival , Anda Skeja , Bei Wang , Ling Zhou

In this paper, we propose a deterministic algorithm that approximates the optimal path cover on weighted undirected graphs. Based on the 1/2-Approximation Path Cover Algorithm by Moran et al., we add a procedure to remove the redundant…

Numerical Analysis · Mathematics 2021-01-25 Junyuan Lin , Guangpeng Ren

An embedding of a graph on an orientable surface is orientably-regular (or rotary, in an equivalent terminology) if the group of orientation-preserving automorphisms of the embedding is transitive (and hence regular) on incident vertex-edge…

Combinatorics · Mathematics 2023-11-17 Stefan Gyurki , Sona Pavlikova , Jozef Siran

In this paper we describe a physical problem, based on electromagnetic fields, whose topological constraints are higher dimensional versions of Kirchhoff's laws, involving $2-$ simplicial complexes embedded in $\mathbb{R} ^3$ rather than…

Combinatorics · Mathematics 2017-11-17 Hariharan Narayanan , H. Narayanan

We investigate the problem of constructing planar drawings with few bends for two related problems, the partially embedded graph problem---to extend a straight-line planar drawing of a subgraph to a planar drawing of the whole graph---and…

Computational Geometry · Computer Science 2014-10-31 Timothy M. Chan , Fabrizio Frati , Carsten Gutwenger , Anna Lubiw , Petra Mutzel , Marcus Schaefer

Computational topology is an area that revisits topological problems from an algorithmic point of view, and develops topological tools for improved algorithms. We survey results in computational topology that are concerned with graphs drawn…

Computational Geometry · Computer Science 2017-09-06 Éric Colin de Verdière
‹ Prev 1 3 4 5 6 7 10 Next ›